title: Cluster-tic syndrome: a cross-sectional study of cluster headache patients.
abstract: OBJECTIVE
  To determine the prevalence and nature of trigeminal neuralgia in a large group of cluster headache patients.
  
  
  BACKGROUND
  Cluster-tic syndrome is a rare headache syndrome in which trigeminal neuralgia and cluster headache co-occur. The existence of cluster-tic syndrome as a separate entity is questioned, and figures on prevalence of simultaneous existence of cluster headache and trigeminal neuralgia are not available.
  
  
  METHODS
  As part of a nationwide study on headache mechanisms in cluster headache (Leiden University Medical Centre Cluster headache Neuro Analysis programme), we collected clinical data of 244 cluster headache patients using a semistructured telephone interview in a cross-sectional design.
  
  
  RESULTS
  In 11 (4.5%) cluster headache patients, attacks fulfilling International Headache Society criteria for trigeminal neuralgia were also present. In all cases, trigeminal neuralgia occurred ipsilateral to cluster headache and in the majority (82%) in the ophthalmic branch. In 8 of these 11 patients (73%), the frequency and time pattern of trigeminal neuralgia seemed to parallel cluster headache and was likely a part of the cluster headache spectrum. In the 3 remaining patients, cluster headache and trigeminal neuralgia were unrelated in time and appeared to occur independently.
  
  
  CONCLUSIONS
  Trigeminal neuralgia co-occurred in 11/244 (4.5%) of cluster headache patients. In only 3 (1.2%) patients, trigeminal neuralgia seemed to occur independently from cluster headache episodes. Trigeminal neuralgia (-like) attacks in cluster headache patients are most of the time part of the cluster headache spectrum and should then probably not be treated separately. A shared underlying pathophysiological mechanism of cluster headache and trigeminal neuralgia is not supported by this study.
authors.affiliation: Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands; Department of Neurosurgery, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: Leopoldine A
authors.initials: LA
authors.lastname: Wilbrink
authors.forename: Claudia M
authors.initials: CM
authors.lastname: Weller
authors.forename: Carlo
authors.initials: C
authors.lastname: Cheung
authors.forename: Joost
authors.initials: J
authors.lastname: Haan
authors.forename: Michel D
authors.initials: MD
authors.lastname: Ferrari
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003027:Cluster Headache / Q000175:diagnosis* / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D020323:Tics / Q000175:diagnosis* / Q000453:epidemiology*; D014277:Trigeminal Neuralgia / Q000175:diagnosis* / Q000453:epidemiology*
keywords: cluster headache; cluster-tic syndrome; trigeminal neuralgia